THE FORELAND THRUST BELT IN NORTHWESTERN MARGIN OF YANGTZE PLATFORM AND THE COALFIELD STRUCTURE FEATURE

The accumulation and occurrence of coal resources in Yangtze platform and its northwest margin are controlled by the formation and evolution of foreland thrust belt in its northwest margin.The foreland thrust belt can be divided into root zone,middle zone and front zone.There is no coal accumulation in root zone,the industrial coal resources are occurred in middle zone,and the coal resources occurred in the front zohe are buried deeply.The coalfield structure deformation which is characterized by the imbricate thrusts,duplex thrust,parallel fold,inclined fold,klippen,thrust sheets and fault block,is resulted from the compressive stress of foreland thrust belt.The formation of the thrust belt is the result of long-time evolution of Tethys domain,in which the plates had collided three times along three sutures.